Recent reports propose a correlation between parents, especially mothers who smoke, and unexplained infant deaths. This correlation fails, however, when groups who do not smoke experience a death rate equal to the population as a whole. Also, cultures known to smoke heavily, like Japan, have practically no incidence of unexplained infant deaths. In particular, Japan did not experience a problem, until recently, in spite of smoking. A case might be made that Western traditions, such as the introduction of PVC and fire retardants into crib mattress, in place of the customary futon, may be the culprit rather than the widespread incidence of smoking. Neither smoking or any other risk factor can account for the fact that a second or third child has a greater risk of becoming a victim  than a first child.  When the growing number of incidents of  taking place in daycare centers and in the homes of Afro-Americans is considered the only risk factor that makes any sense at all is the re-use of older baby mattresses.  Ironically, old mattresses have not yet made the medically accepted list of risk factors, in spite of the fact the Scotland Cot Death Foundation has reported as recently as February 2000 that the risk of unexplained infant death is three times greater on used mattresses.  This report can be found in the proceedings of the Sixth International SIDS Conference.